District Judge Mark Wolf said Michelle Kosilek, who lives as a woman in an all-male prison, was entitled to the state-funded sex realignment surgery because it was the “only adequate treatment” for Kosilek’s “serious medical need.”

Reuters reported that Kosilek, who has suffered from gender identity disorder since he was a child, has been taking hormones that have caused his breasts to grow.

Kosilek began suing the Massachusetts Department of Correction in 2000, arguing he also needed a sex change operation.

"In this case Kosilek has proven that he still has a severe gender identity disorder. Although female hormones have helped somewhat, he continues to suffer intense mental anguish because of his sincere and enduring belief that he is a female trapped in a male body," Wolf wrote in the landmark 126-page judgment.